Clutch and brake cylinder O ring?

[1200ts]

What size is the O ring for the clutch and brake plastic reservoir to master cylinder? Mine is starting to leak. Bike is a RGS.

 

[bobsotto]

I ordered a BS126 EPDM O-ring with the dimensions 34.6 mm ID and 2.62 mm cross section ( 1.375" and 0.103") for my RGS.
Regards Arne